A Study on Tsunami Protection Measures of Mooring Vessels to a Wharf by Install More Mooring Tethers (Part 1)

When the tsunami attacks in harbors, the vessels moored at a wharf may be unable to be evacuated. For example, it may happen the situations that the vessel is under cargo handling, the vessel has no crew or only foreign crew without knowledge of tsunami. In such a case, the following damages are assumed; breaking the mooring tether, grounding on a wharf, drifting to land areas and destroying buildings. This present paper describes the tsunami simulation and the motion analysis of vessel moored at a wharf using the MPS method (Moving Particle Semi-implicit method). In this research, the 3D-MPS method is applied. The chart of break of mooring tethers was created. The wave height of tsunami, draft of vessels and the relation of the break of the mooring tether were shown by the chart of break of mooring tethers. Then, the chart of break of mooring tethers is proposed for various scale of tsunami including the effect of incident angle of the mooring tether can be easily estimated against to the scale of tsunami and mooring system.